Naga is with Bolin right now... Korra left her with Bolin when she went to go confront Mako.
And when Korra went missing last time when Tarrlok kidnapped her it was Naga who went looking and found her.
What if all of them are sitting around (Bolin, Mako, Asami) and all of a sudden Naga just senses something. She starts acting restless and nobody can seem to figure out why. Varrick is getting frustrated because Naga won't cooperate during filming and it's starting to delay the production... something that costs Varrick money and causes him to become upset (maybe start revealing his true nature to Bolin). Even Pabu senses Naga's unease and starts acting strange. Naga will walk around like she's looking for something and often times Pabu will join in. Every now and then Naga thinks she smells something and she'll start going crazy, howling and running around. Bolin tries to gently calm her but it's no use.
Then one day a frustrated Mako walks in to the production room and notices Bolin's failing attempts to calm Naga. He notices a look of fear and desperation in Naga's eyes - one he's seen before. Every time something happens to Korra, Naga knows. She just knows. And this time Mako gets really nervous. He knows Korra can be irrational at times and he also feels the sting of guilt from their last words and breakup. With a sinking gut feeling he runs over to Bolin who's still ignoring him.
"Bolin this is about Korra! I think Naga's going insane because something happened to her!" Mako finally shouts.
This causes Bolin to pause. While he's upset at Mako he has no quarrel with Korra and the thought of her missing again deeply concerns him. He snaps out of his movie start persona and looks at his brother with worried eyes.
"What do you think happened to her, Mako?"
"I don't know," Mako says with a hint of desperation. "Maybe we should let her roam and see where she takes us."
The brothers agree and start to follow Naga as she leaves the building (much to Varrick's dismay) and starts looking for a smell. She reaches the shoreline of Republic City and begins to howl loudly.
"Is she out in the water?" Mako looks frantically at the polar bear dog.
Suddenly Bolin's eyes widen, "the plan!"
Mako whips around, "what plan?!" he asks angrily remembering Korra's last plans to break out on her own.
"Well I know she was going to talk to General Iroh..." Bolin said trying to gather his thoughts.
"I already know that!" Mako hissed. "We need to find Iroh. He may know something more."
The two brothers convince Naga to head over to the docks where the United Forces are docked. The ships stand as a beacon of strength but as Mako gets closer and gets enveloped by the shadow, a feeling of darkness overcomes him. They're only here because of him. If he wouldn't have said anything they'd be at the south pole by now overthrowing Unalaq. Mako knew he had made the right call but with Korra's teary face still burned in his memory, he wondered if maybe he could've gone about things a little bit differently. He agonized as he tried to swallow the lump in his throat. Naga knew something bad happened to Korra and that fight was the last thing she heard from the one person she loved more than anyone. Mako was desperate for one more chance to speak with her. But an awful pit in his stomach told him he might never get that chance.
Iroh had brought out a chair and sat on the deck facing the sun. He looked over the bay as if he was searching for something, his mind preoccupied. It wasn't like him to just sit around and do nothing. Part of the reason Iroh took this position to begin with was the thrill of being able to travel.
"Hey General Iroh!" Bolin waved heartily.
Iroh stood up and smiled. "Good to see you again, Bolin. Mako. Naga," he nodded as he acknowledged everyone in the group. "What can I do for you?"
A fidgety Mako gently pushed his brother aside, "we're looking for Korra. We can't find her and we were wondering if you knew anything about her whereabouts."
Iroh straightened out and thought about it for a moment. "Well when the plan for me to help her fell through, I suggested she go visit my mother, the Fire Lord, and my grandfather." He smiled, "they've always been good friends with the southern water tribe. Korra said she would take me up on my offer. So in that case there's a chance she's at the fire nation royal palace right now," Iroh finished confidently.
Mako breathed a sigh of relief. Honestly that was probably the best case scenario possible. She was safe. But Mako still wanted to see her again. The thought of losing her again, after all they had been through, was enough to wake him up. He turned to Bolin.
"Let's go look for her in the fire nation!"
Bolin suddenly stiffened. "How about you go alone," he replied coldly. Bolin gently tugged on Naga's saddle. "Come on, Naga, we have a film to make."
But Naga wouldn't budge. In fact she was starting to look more distressed than ever. Even Iroh was starting to be concerned.
Then it happened.
"General Iroh I have received some news you should hear about!" an officer said.
"What is it?" Iroh asked turning to face his officer.
"There are multiple rumors going around that while enroute to the fire nation, Avatar Korra was swallowed up by a dark spirit. It is unclear what happened to her but many suspect she did not make it."
The whole world fell away as Mako stood there shaking. An overwhelming sense of grief began to cripple him. He knew this feeling all too well. It was the same grief he felt when he watched his parents die. Was this really happening to him again?
"How…how can you know for sure?" Mako snapped in a raspy voice as he tried to fight back the tears. "You… you don't know... who told you this? Where'd you get your information? Where can I talk to this person who gave you the information?"
The officer glanced down and back up again. "Actually... it was an undercover United Forces officer who told me the news. And he said he heard it from Chief Unalaq directly. He was overheard Unalaq telling his two children to go back out and look for the remains. Unalaq was also overheard strategizing about potentially looking for the next avatar in the earth kingdom."
Just as a tear formed in the corner of Mako's eye he shook his head furiously and ran over to grab Naga's saddle.
"We're going," he told the polar dog firmly. This time Naga hardly put up a fight. In fact, her expression changed to a look of determination as Mako mounted her.
"Let's go." Mako whispered.
"Wait!" Bolin said as he reached out to tug harder on Naga's saddle.
"What?" Mako hissed. "What do you want. You want to gloat? About how you were right? About how I've been treating the people around me? Are you here to tell me about how by taking Naga I'm ruining your stardom and therefore your life? My girlfriend is dead and it's all my fault! If I would've just-"
"Mako!" Bolin yelled to stop his brother. Mako froze and Bolin could tell he was beginning to cry. Mako was taking the news about Korra very hard.
Bolin closed his eyes and took a deep breath. "Look, Mako, I know we haven't been getting along lately but you're still my brother. You need me right now and I will never turn my back on you."
Mako's expression softened and tears began to roll down his face. "Bolin, I-" he started to apologize.
Bolin cut him off gently. "Let's go see if we can find Korra. I for one want to believe she's still alive."
"So do I," Mako whispered as he closed his eyes.
"Good luck," Iroh said quietly. "I really hope you're able to find her. Alive."
And with that Bolin mounted behind Mako on Naga and the two rode off. They arrived just in time to catch the next ship headed for the fire nation.
Somewhere out there was Korra.